The present invention pertains to a metering pump dispenser for the simultaneous, metered dispensing of liquid and/or pasty media from at least two separate storage chambers, which are arranged in a common pump housing and with which separate metering pumps with a priming valve and a dispensing valve each are associated, wherein the metering pumps can be actuated by means of a common actuating member, which is mounted axially movably in the head part of the pump container and has one or more dispensing channels.
In prior-art metering pump dispensers (U.S. Pat. No. 4,773,562) with separate containers for different media, which containers are arranged next to one another with parallel axes, or with coaxially arranged containers for different media (U.S. Pat. No. 4,949,874), in which a separate metering pump is associated with each container, the metering pumps are actuated jointly by an actuating member, which is or can be attached at the top and performs axial movements, during which restoring spring forces are overcome. The actuating members are guided axially, so that the resisting force which counteracts the actuation of the actuating member by the restoring forces and the viscosity of the media to be dispensed, must be applied at a ratio of 1:1.
The actuating forces to be applied may be considerable especially in the case of pasty media which are dispensed in predetermined amounts upon each stroke of the actuating member. It may happen that the actuating member cannot be actuated by one hand, which may not only make it difficult to use such metering pump dispensers with at least two metering pumps and two storage containers but also questionable on the whole.
A metering pump dispenser for the simultaneous, metered dispensing of liquid and/or pasty media from at least two separate storage chambers has also been known (DE 41 20 644 C1), in which the actuating member is mounted in a lever-like manner pivotably in one direction around a pivot bearing in a head part of the pump housing, which said head part axially projects over the storage chamber, to perform limited pump strokes. The metering pumps each have bellows as a pumping member, which is connected to a pump housing on the housing side and to the common actuating member on the dispensing side.
Each metering pump is provided here with a priming valve and a dispensing valve, via which the storage chambers are in connection with one or more dispensing channels. The dispensing channels are arranged in this metering pump dispenser directly in the actuating member such that they end in a common plane of a dispensing nozzle. The pivot axis of the pivot bearing is arranged at right angles to a common symmetry plane of the metering pumps such that the metering pumps are located at different distances from the pivot axis and have different effective lever arms relative to the pivot axis and perform different pump strokes, which are at a fixed, preselectable ratio to one another, simultaneously and in the same direction during the actuation of the actuating member.
While the two metering pumps are actuated uniformly during each pump stroke in the case of the metering dispenser of this class, the pump strokes of the two metering pumps are fundamentally different in this prior-art metering pump dispenser because the actuating member is designed and mounted as a one-armed lever.
The primary object of the present invention is to provide a metering dispenser of the type mentioned in the introduction, whose actuating member can be actuated manually by applying a weaker force.
This object is accomplished according to the present invention by a pivoted lever, which is pivotable around a pivot axis extending at right angles to the housing axis, acts axially with a short lever arm on the actuating member at least approximately in the central plane located between the metering pumps and can be actuated manually by means of a longer lever arm, being mounted in a head part section of the pump housing, which said head part section is extended beyond the actuating member.
By using an additional pivoted lever, via which the axially movable actuating member, which uniformly actuates both metering pumps, is moved, the force to be applied for the actuation is considerably reduced as a consequence of the different lever arms that now become effective. This reduction makes it possible to perform the actuation of the actuating member by means of the pivoted lever relatively easily with one finger of the hand, which holds the pump housing and the entire metering dispenser during its use.
Due to the arrangement provided, it is readily possible to obtain a lever arm ratio of 2:1, which means that the force that must be applied to actuate the actuating member via the pivoted lever is half the force acting directly on the actuating member.
Thus, the user of such a metering dispenser has the feeling that he is actuating only one metering pump.
This favorable lever arm ratio is facilitated by the elliptical cross-sectional shape of the pump housing and the arrangement of the pivoted lever in the longitudinal axis of the elliptical shape.
A possible design feature with the separate housing part adapted to the cross-sectional shape of the said pump housing, which separate housing part can be lockingly attached to the upper end section of the said pump housing and has an opening for movably accommodating the said dispensing channel or dispensing channels of the actuating member, may be provided to make it possible to manufacture and especially mount the head part section in a simple manner.
The possible embodiment of the present invention, in which the housing part has two mounting supports with coaxial sockets in one half of the housing under a closed front wall section in a symmetrical arrangement in relation to an axial central plane of the housing and a said button opening, which is located in the plane of the front wall section and is extended in a recess of the axial wall is provided in the other half of the housing, leads not only to a favorable arrangement and mounting of the pivoted lever, but also to the advantage that the opening necessary for the actuation of the pivoted lever in the housing part can be closed in the inoperative position of the pivoted lever. The provision of a transverse wall and an additional side wall also serve this purpose.
The possible embodiments in which the housing part has two guide walls, which are arranged symmetrically to the axial central plane of the housing and extend in parallel to the plane, as a lateral limitation of the front-side button opening and for laterally guiding the said pivoted lever and an arched wall apron extends at least over the range of movement of a said button surface of the pivoted lever, guarantee that the opening of the housing part forming the head part section, in which the pivoted lever is accommodated, also remains largely closed during the actuation of the pivoted lever. This is also important because as a result, the actuating finger or fingers of the user cannot come into contact with any edges of the housing, which could cause jamming or even cutting, during the actuation of the pivoted lever.
A functionally favorable, low-friction transmission of forces between the pivoted lever and the actuating member, on the front surface of which the pivoted lever acts via the cam-like, arc-shaped projections provided may also be provided.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.